Collecting Grant Morrison’s sweeping "Planet X" storyline (New X‑Men #146–150), this edition reveals Cyclops’s devastating discovery: Professor X has been replaced by the malevolent Xorn. As X‑Men contend with betrayal and the machinations behind Xorn’s hidden agenda, trust fractures and alliances crumble. The arc culminates in a brutal final showdown in Tian, China, testing loyalties and reshaping the Xavier legacy.